clogl

SYNOPSIS

DESCRIPTION

The logarithm clog() is the inverse function of the exponential
cexp(3). Thus, if y=clog(z), then z=cexp(y). The imaginary part
of y is chosen in the interval [-pi,pi].
One has:
clog(z) = log(cabs(z)) + I * carg(z)
Note that z close to zero will cause an overflow.